Previously, as a combustor which allows for size reduction, a combustor is known which burns combustion gas (an air-fuel mixture that mixes fuel and oxidants) that is emitted from a first pipe via apertures that are within a flame quenching distance in a combustion region within a second pipe.
According to this type of combustor, flame propagation to the first pipe is prevented by the apertures that are within the flame quenching distance. Furthermore, by conducting appropriate supply of combustion gas, it is possible to stably burn combustion gas in an extremely narrow combustion region within the second pipe.
Now, with respect to the combustor, when combustion gas is burned in the combustion region, the flame in the combustion region is maintained by continuously supplying combustion gas to the combustion region. However, at the time of start-up, it is necessary to ignite the combustion gas with an ignition apparatus.
Consequently, the combustor is configured with disposal of an igniter plug (flame kernel formation unit) of the ignition apparatus on the downstream side of the combustion region. Ignition of combustion gas at the time of start-up is then conducted using a flame kernel formed by the igniter plug (see, e.g., Patent Document 1).
Furthermore, as this type of combustor, for purposes of more stable burning of combustion gas, further size reduction of the combustor, and advancement of energy efficiency, a combustor has been proposed that heats combustion gas prior to burning by transferring the heat of burned gas that arises from burning of combustion gas to the combustion gas via a first pipe (see, e.g., Patent Document 2).